Addressing backers in an overly warm ballroom in Roanoke, Virginia, the Republican presidential nominee on Monday lashed out at Clinton as low-energy and needing naps. He argued that she dropped her maiden name of Rodham because it sounds like Rotten.

The event was held in the home state of Clinton's new running mate, Sen. Tim Kaine, whom Trump derided as a "weird little dude" and a political "hack." Trump argued that Clinton made a mistake when she chose Kaine, describing the well-liked former governor and senator as the opposite of a fiery liberal that supporters of Clinton's former rival Bernie Sanders may have been drawn to.

Many of Sanders' supporters remain deeply committed to their candidate, holding demonstrations in Philadelphia and booing mentions of Clinton on the convention floor.

But most of Trump's speech focused on Clinton. The billionaire businessman unleashed a barrage of attacks against Clinton in light of the latest scandal to overshadow her run for office, accusing her of disloyalty for not protecting outgoing Democratic National Committee Chairwoman Debbie Wasserman Schultz following the release of hacked emails that suggest some DNC staffers favored Clinton over Sanders.

Trump claims Wasserman Schultz "worked very hard to rig the system" in Clinton's favor, and that Clinton responded by throwing her "under the bus."

He also suggested at one point that China may have been involved in the DNC hack, despite no evidence to suggest the country's involvement.

"Little did she know that China, Russia — one of our many, many friends — came in and hacked the hell out of us," Trump said sarcastically, framing the words "friends" in air quotes.

After Democratic Party officials learned their systems were attacked in late April, they sought the help of the cybersecurity firm CrowdStrike Inc., which then discovered traces of at least two sophisticated hacking groups on the Democrats' network — both of which have ties to the Russian government.

The FBI said Monday it is investigating how the hack occurred.

Trump's campaign has dismissed suggestions that the Russians may be trying to influence the election in his favor.

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